Right Angle Finderscope; Recommendations?

[Rodstar]

With the delivery of my new scope imminent (:D ), I have started thinking about finderscopes. SDM (www.sdmtelescopes.com.au) do offer these, but I am thinking I might sample the range of what is out there before settling on any particular one, SDM or otherwise.

My perameters are:

1. FOV of at least 5 degress
2. Light weight (bearing in mind balance issues with a 20" dob)
3. Right angle (to spare me from a sore neck)
4. Able to be removed easily for transportation (secondary cage has a fitted case)
5. Focuser
6. Correct image
7. Able to use 1.25" EPs
8. Dew shield / extended front tube
9. In keeping with style of my SDM scope (I was thinking brass ;) )

I have noticed Takahashi put out some excellent finderscopes, but not sure if they can be coupled with a diagonal??

Any thoughts / comments/ experiences much appreciated.:thumbsup:

[CoombellKid]

Why dont you just get yourself a ED80 or something similar. That way
you can either have it straight through or right angled. I dont suppose
you will be starhopping with it? starhopping is a real pain to do quickly
with a right angled finder.

oooop's I see you already have one.

[Dennis]

Hi Rod

A bit of a ramble, but here goes. I have an Orion 9x50 RA finder scope I purchased from Bintel a couple of years ago for use on my Vixen 4” f9 refractor. The finder bracket/stalk has the standard dovetail that fitted the Vixen mount, although the fit was not as good as the Vixen finder bracket/stalk.

I really thought that the RA would be the answer to all my “finding” problems, but it wasn’t. The main reason is that with the Vixen straight through finder scope, I can squint along the 7x50 tube whilst pressing my motor movement buttons, to get to the field that I want. With the RA finder, the RA assembly blocks this view and also, the tube is much shorter so squinting is not as accurate and reliable.

In the end, I fitted both finders to the OTA as the focuser has two extra pre-drilled and tapped holes to fit a dovetail shoe on the RHS as well as the already fitted shoe on the LHS. So, now, I squint along the straight through finder to get the field I want and then I centre the alignment object using the RA finder.

I suspect the combination of a Red Dot finder and a RA finder would also be quite useful.

The Orion finder is okay and good value for the money, but the fit and finish are well below the Vixen supplied finder and I have heard of people having to file down the stalk dovetail pin to allow it to slide into the dovetail bracket – there is a lot of paint on this gear, so maybe the raw metal to metal surfaces fitted okay, but the paint layers cause binding. One thing I really like about the Orion finder is the use of 2 nylon adjustment screws, with the third point being some kind of spring loaded piston, so the finder is a dream to align.

The only RA illuminated finder I know of is the one at Scopestuff (http://www.scopestuff.com/ss_find1.htm) by Antares.

I also have a beautiful 9x50 finder that I purchased from Ron at Sirius Optics (http://www.sirius-optics.com.au/finder_scopes.htm). It is illuminated but is unfortunately straight through only. The optics are really nice and the illuminated reticule terminates in a small circle at the centre, so that when you place a star in this circle, the cross hairs do not hide it as in my Orion and Vixen finders. Also, the Sirius unit has very fine cross hairs with ticks at 1 degree intervals. It cost me around $300 but it has proven its worth over the years. Unfortunately, the last time I was in the shop, Ron had sold out.

Hope that helps.

Cheers

Dennis

[[1ponders]]

Have a look at the Stellarvue finders (http://www.optcorp.com/productList.aspx?uid=&pg=3&kw=Stellarvue&st=2)here Rod. They pretty well match up for all your requirements. The 5 deg FOV will depend on the eyepiece you use. I have the SV-F50B2 and it's great.

[Rodstar]

Rob: Yeah, I have an ED80, and it is too heavy to go on the secondary cage. Peter Read has something similar to the size on an ED80 mounted to his mirror box. Not my cup of tea because I want to use it while up the ladder to find things!

Dennis: Thanks for the info about your experiences with the Orion option. I had thought it looked a tad cheap and nasty. I will have a Telrad for direct pointing. The finderscope is more to help me work through galaxy clusters and hopping through familar fields to find objects of interest rather than only using the Argo Navis. I don't know much about the Antares brand. I get the feeling it would be of similar quality to the Orion, but I have no info to go by at this stage.

Paul: the Stellarvue finders looks just the thing! Did you get yours through Optcorp? What did you pay in freight from the US?

[[1ponders]]

Yes through OPT. I got the finder and the bracket and postage (here in about 4 day :eyepop: ) for $204 US. I'm an OPT member so I get a discount, the postage was about $45, but I paid the premium rate to get it here quicker.

[Rodstar]

That sounds very dangerous, Paul! Once you are a member, I dare say you would want to make the most of your membership!:scared:

Just found a Cloudy Nights write up about the original Stellarvue 50mm finder: http://www.cloudynights.com/item.php?item_id=1324

Sounds like a very good line of finders.